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State-of-the-art for evaluating the potential impact of tectonism and volcanism on a radioactive waste repository (open access)

State-of-the-art for evaluating the potential impact of tectonism and volcanism on a radioactive waste repository

Most estimates of the time required for safe isolation of radioactive wastes from the biosphere range from 100,000 to 1,000,000 years. For such long time spans, it is necessary to assess the potential effects of geologic processes such as volcanism and tectonic activity on the integrity of geologic repositories. Predictions of geologic phenomena can be based on probabilistic models, which assume a random distribution of events. The necessary historic and geologic records are rarely available to provide an adequate data base for such predictions. The observed distribution of volcanic and tectonic activity is not random, and appears to be controlled by extremely complex deterministic processes. The advent of global plate tectonic theory in the past two decades has been a giant step toward understanding these processes. At each potential repository site, volcanic and tectonic processes should be evaluated to provide the most thorough possible understanding of those deterministic processes. Based on this knowledge, judgements will have to be made as to whether or not the volcanic and tectonic processes pose unacceptable risk to the integrity of the repository. This report describes the potential hazards associated with volcanism and tectonism, and the means for evaluating these processes.
Date: July 16, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Cause of pitting in beryllium (open access)

Cause of pitting in beryllium

Light microscopy, bare-film radiography, secondary ion mass spectroscopy, electron microprobe and physical testing were used to examine beryllium specimens exhibiting a stratified, pitted, pattern after chemical milling. The objective was to find the cause of this pattern. Specimens were found to have voids in excess of density specification allowances. These voids are attributed, at least in part, to the sublimation of beryllium fluoride during the vacuum hot pressing operation. The origin of the pattern is attributed to these voids and etching out of fines and associated impurities. Hot isostatic pressing with a subsequent heat treatment close residual porosity and dispersed impurities enough to correct the problem.
Date: April 16, 1982
Creator: Kershaw, R. P.
Object Type: Article
System: The UNT Digital Library
State-of-the-art for evaluating the potential impact of flooding on a radioactive waste repository (open access)

State-of-the-art for evaluating the potential impact of flooding on a radioactive waste repository

This report is a review of the state-of-the-art for evaluating the potential impact of flooding on a deep radioactive-waste repository, namely, for predicting the future occurrence of catastrophic flooding and for estimating the effect of such flooding on waste containment characteristics. Several detrimental effects are identified: flooding can increase groundwater seepage velocities through a repository within the framework of the existing hydrologic system and thus increase the rate of radioactive-waste leakage to the biosphere; flooding may alter repository hydrology by reversing flow gradients, relocating sources of groundwater recharge and discharge, or shortening seepage paths, thereby producing unpredictable leakage; saturation of a vadose-zone repository during flooding can increase groundwater seepage velocities by several orders of magnitude; and flooding can damage repository-media containment properties by inducing seismic or chemical instability or increasing fracture permeability in relatively shallow repository rock as a result of redistributing in-situ stresses. Short-term flooding frequency and magnitude can be predicted statistically by analyzing historical records of flooding. However, long-term flooding events that could damage a permanent repository cannot be predicted with confidence because the geologic record is neither unique nor sufficienly complete for statistical analysis. It is more important to identify parameters characterizing containment properties (such as permeability, …
Date: July 16, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Bumps and poles in the S-matrix: A systematic study of 0 sup ++ and 2 sup ++ mesons plus a molecule approach to the E(1420) in the K K. pi. system (open access)

Bumps and poles in the S-matrix: A systematic study of 0 sup ++ and 2 sup ++ mesons plus a molecule approach to the E(1420) in the K K. pi. system

The goal of Hadron Spectroscopy is to find the spectrum of states formed by color singlet arrangements of quarks and gluons. Ideally these spectral states are associated with poles of the scattering matrix of hadrons which are the decay channels of the states. For example the {rho} meson is the lowest q{bar q} s-wave, spin one color singlet state and decays into {pi}{sup +}{pi}{sup -}. Since the {rho}decays in a relative p-wave, one finds the {rho} pole in the I = 1 p-wave {pi}{pi} phase shifts. There are forces between quarks and gluons which do not manifest themselves as true resonances and thus cannot be described by a Breit-Wigner pole. I will give some examples that are not Breit-Wigner poles of the scattering matrix but are important bumps in meson production. 22 refs., 10 figs.
Date: November 16, 1989
Creator: Longacre, R. S.
Object Type: Article
System: The UNT Digital Library
Oxidation/gasification of carbon residue on retorted oil shale. Final report (open access)

Oxidation/gasification of carbon residue on retorted oil shale. Final report

Studies of the oxidation and gasification of oil shale char were extended to an investigation of the effects of mineral catalysis. Six shales with differing mineral compositions were studied, including samples from the saline zone in the Western Colorado and from the Antrim shales of Michigan. Oxidation kinetics data, corrected for mass transfer effects, were compared for all six samples. A high assay shale from Utah and a sample from the saline zone were found to have the highest oxidation rates. By examining the data for shales which were water leached and thermally pretreated, it was concluded that both NaO and CaO act as oxidation catalysts. However, as a result of mineral decomposition experiments conducted with a sample from the C-a lease tract, it appears as though the ankeritic dolomite fraction will not decompose as long as there is a minimal CO/sub 2/ over pressure. Rather, low temperature silication reactions appear to take place once the temperature exceeds 925/sup 0/K. An extensive evaluation was also completed for the gasification of an Antrim shale from Michigan. Both the rates of CO/sub 2/ and steam gasification of the char were found to be markedly lower than that observed for a shale sample …
Date: January 16, 1984
Creator: Thomson, W. J.
Object Type: Report
System: The UNT Digital Library
State-of-the-art for evaluating the potential effects of erosion and deposition on a radioactive waste repository. Final report (open access)

State-of-the-art for evaluating the potential effects of erosion and deposition on a radioactive waste repository. Final report

The potential impact of future geologic processes on the integrity of a deep, high-level radioactive-waste repository is evaluated. The following study identifies the potential consequences of surface erosion and deposition on sub-surface repository containment characteristics and assesses the ability to measure and predict quantitatively the rates and corresponding extent of these processes in the long term. Numerous studies of the magnitudes and rates of surficial erosion and deposition that have been used to determine the minimum allowable depth for a geologic repository (300 m - NRC Code of Federal Regulations, Part 60.122, Draft 10) are cited in this report. Measurement and interpretation of potential rates and extent of surficial processes in these studies involved considerable uncertainty, and the implications of this uncertainty on presently proposed repository siting criteria are addressed herein. Important concepts that should be considered when developing siting criteria to protect against deleterious effects arising from future erosion or deposition are highlighted. Erosion agents that could affect deep repositories are distinguished in this report so that their individual and combined impacts may be examined. This approach is recommended when evaluating potential repository sites in diverse environments that are susceptible to different agents of erosion. In contrast, agents of …
Date: July 16, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
RODCON: a finite difference heat conduction computer code in cylindrical coordinates (open access)

RODCON: a finite difference heat conduction computer code in cylindrical coordinates

RODCON, a finite difference computer code, was developed to calculate the internal temperature distribution of the fuel rod simulator (FRS) for the Core Flow Test Loop (CFTL). RODCON solves the implicit, time-dependent forward-differencing heat transfer equation in 2-dimensional (Rtheta) cylindrical coordinates at an axial plane with user specified radial material zones and surface conditions at the FRS periphery. Symmetry of the boundary conditions of coolant bulk temperatures and film coefficients at the FRS periphery is not necessary.
Date: September 16, 1980
Creator: Conklin, J. C.
Object Type: Article
System: The UNT Digital Library
Probing the possibility of a /sup 12/C/sup 13/C abundance gradient from observations of interstellar CH/sup +/ (open access)

Probing the possibility of a /sup 12/C/sup 13/C abundance gradient from observations of interstellar CH/sup +/

I have performed high signal-to-noise (SN /equals/ 300 to 500) observations of interstellar CH/sup /plus// at Lick Observatory and at CTIO of the reddened, early-type stars HD 183143, HD 24432, and HD 157038 in an effort to probe the existence of a /sup 12/C/sup 13/C abundance gradient in our Galaxy.
Date: September 16, 1987
Creator: Hawkins, I.
Object Type: Article
System: The UNT Digital Library
Recommended new criteria for the selection of nuclear waste repository sites in Columbia River basalt and US Gulf Coast domed salt (open access)

Recommended new criteria for the selection of nuclear waste repository sites in Columbia River basalt and US Gulf Coast domed salt

Screening criteria and specifications are recommended to aid in the evaluation of sites proposed for nuclear waste disposal in basalt and domed salt. The recommended new criteria proposed in this report are intended to supplement existing repository-related criteria for nuclear waste disposal. The existing criteria are contained in 10 CFR 60 sections which define siting criteria of the Nuclear Regulatory Commission (NRC), and ONWI 33(2) which defines siting criteria of the Office of Nuclear Waste Isolation (ONWI) for the Department of Energy. The specifications are conditions or parameter values that the authors recommend be applied in site acceptance evaluations. The siting concerns covered in this report include repository depth, host rock extent, seismic setting, structural and tectonic conditions, groundwater and rock geochemistry, volcanism, surface and subsurface hydrology, and socioeconomic issues, such as natural resources, land use, and population distribution.
Date: June 16, 1980
Creator: Steinborn, T.L.; Wagoner, J.L.; Qualheim, B.; Fitts, C.R.; Stetkar, R.E. & Turnbull, R.W.
Object Type: Report
System: The UNT Digital Library
Small Angle Physics at CDF: A Progress Report (open access)

Small Angle Physics at CDF: A Progress Report

In 1989 CDF collected data in special high beta runs with a trigger selecting elastic and inelastic events in order to measure the total cross section ({sigma}{sub tot}) and the differential elastic cross section (d{sigma}{sub el}/dt). Data were taken at cms energies of 300, 540, 1000 and 1800 GeV. A double arm magnetic spectrometer located along the beam pipe tags the particles scattered at very small angles and tracking detectors surrounding the interaction point reveal particles produced at larger angles. We discuss the status of the analysis of elastic and inelastic events with emphasis on the event selection and the background subtraction. 5 refs., 14 figs., 3 tabs.
Date: December 16, 1989
Creator: Paoletti, Riccardo
Object Type: Article
System: The UNT Digital Library
Proposed method of assembly for the BCD silicon strip vertex detector modules (open access)

Proposed method of assembly for the BCD silicon strip vertex detector modules

The BCD Silicon strip Vertex Detector is constructed of 10 identical central region modules and 18 similar forward region modules. This memo describes a method of assembling these modules from individual silicon wafers. Each wafer is fitted with associated front end electronics and cables and has been tested to insure that only good wafers reach the final assembly stage. 5 figs.
Date: October 16, 1989
Creator: Lindenmeyer, C.
Object Type: Report
System: The UNT Digital Library
Comparative analysis of internal fuel motion in annular fuel designs (open access)

Comparative analysis of internal fuel motion in annular fuel designs

In this paper, the whole-core reactivity consequences of internal fuel motion in three annular fuel designs during a hypothetical 3 dollars/s transient overpower (TOP) accident are compared to determine the effect of geometric design variations. The PINEX-2 and PINEX-3 experiments were performed in the TREAT reactor using annular fuel pins irradiated in GETR. This paper investigates three combinations of solid and annular axial blankets and fission gas plena: top annular blanket and plenum, bottom annular blanket and plenum, and both top and bottom (dual) annular blankets and plena. The dual plena design case showed a significant decrease in internal fuel motion over the single plenum design cases.
Date: September 16, 1983
Creator: Smith, D. E.
Object Type: Article
System: The UNT Digital Library
Development of a solar-desiccant dehumidifier. Phase II second technical progress report (open access)

Development of a solar-desiccant dehumidifier. Phase II second technical progress report

The solar desiccant air conditioner (SODAC) system and its operation are described, including the characteristics of the major components, the performance at design conditions, and the control schemes for optimum operation in various climates. The system uses granular silica gel as a desiccant. It may operate in either a recirculated mode (no air exchange between the outside and the conditioned space) or a ventilated mode (air exchanged between outside and conditioned space). The test data in the ventilated mode at design flow rates are presented. Data include outdoor and indoor inlet wet and dry bulb temperatures, indoor outlet dry and wet bulb temperatures, capacity, coefficient of performance, air flow rates, hot water temperature, and solar heat used. The effects of indoor, outdoor, and hot water temperatures on the capacity and coefficient of performance are shown graphically, and the recirculated and ventilated modes, performances are compared. (LEW)
Date: October 16, 1981
Creator: Rousseau, J.
Object Type: Report
System: The UNT Digital Library
Laser-assisted solar cell metallization processing. Quarterly report, September 13-December 12, 1983 (open access)

Laser-assisted solar cell metallization processing. Quarterly report, September 13-December 12, 1983

The Westinghouse Electric Corporation has undertaken to investigate, develop, and characterize laser-assisted processing techniques utilized to produce the fine line, thin metal grid structures that are required to fabricate high-efficiency solar cells. Two basic techniques for metal deposition will be investigated, as follows: (1) photochemical decomposition of liquid or gas phase organometallic compounds utilizing either a focused, CW ultraviolet laser (System 1) or a mask and ultraviolet flood illumination, such as that provided by a repetitively pulsed, defocused excimer laser (System 2), for pattern definition, and (2) thermal deposition of metals from organometallic solutions or vapors utilizing a focused, CW laser beam as a local heat source to draw the metallization pattern. The purpose of this contract is to investigate the various existing laser-assisted film deposition techniques in order to develop a new, cost-effective technology for solar cell metallization. The tasks that will be performed in the conduct of these investigations are detailed. In the first three months of this contract, a comprehensive literature search has been carried out on the various state-of-the-art laser-assisted techniques for metal deposition, including laser chemical vapor deposition and laser photolysis of organometallics, as well as laser-enhanced electroplating. A compact system for the experiments involving …
Date: January 16, 1984
Creator: Dutta, S.
Object Type: Report
System: The UNT Digital Library
Development of molten carbonate fuel cell power plant. Quarterly progress report, February 1, 1982-April 30, 1982 (open access)

Development of molten carbonate fuel cell power plant. Quarterly progress report, February 1, 1982-April 30, 1982

Work proceeded this quarter mainly under three program tasks. Under Task 1.0, work was started on preparing a description of the reference Steam Injection System. It is planned to lay out the plant in power unit trains rated at a nominal 100 MW(e). Under Task 2.0, work continued on anode, cathode, current collector, and electrolyte tile develoment and stack design and analysis. Corrosion test results of various current collector materials after 3500 hours exposure are reported. Sintering data at 6000 hours were obtained on twelve different material samples tested to evaluate the effects of chromium and ceramic addition to state-of-the-art and in-house fabricated electrodes. The 6000 hour data showed no change in porosity or pore distribution from the 5000 hour data. The electroless-plated ceramic plaques demonstrated good stability and porosities. Two cells containing dual porosity anodes using all metal-plated-ceramic material, were tested. Although testing was terminated due to cracked tiles, the cell results are encouraging for the experimental anodes. Under Task 4.0, work continued on installation and debugging of the atmospheric bench scale single cell test facility, and operation of a cell started on April 20, 1982. Progress is detailed. (WHK)
Date: June 16, 1982
Creator: unknown
Object Type: Report
System: The UNT Digital Library
New concept for a high-power beam dump (open access)

New concept for a high-power beam dump

A new concept for a dump for the ion and neutral beams used in the controlled nuclear fusion program uses thin sheets of a refractory metal such as tungsten formed into troughs having semi-circular cross sections. High-velocity water flowing circumferentially removes heat by subcooled nucleate boiling. Possible advantages are modular construction, lower water-pumping power, and a lower pressure drop than in conventional beam dumps. An example design calculation is shown for a dump capable of absorbing an incident flux of 10 kW/cm/sup 2/.
Date: April 16, 1980
Creator: Moir, R.W. & Taylor, C.E.
Object Type: Article
System: The UNT Digital Library
Magnetic shielding tests for MFTF-B neutral beamlines (open access)

Magnetic shielding tests for MFTF-B neutral beamlines

A test program to determine the effectiveness of various magnetic shielding designs for MFTF-B beamlines was established at Lawrence Livermore National Laboratory (LLNL). The proposed one-tenth-scale shielding-design models were tested in a uniform field produced by a Helmholtz coil pair. A similar technique was used for the MFTF source-injector assemblies, and the model test results were confirmed during the Technology Demonstration in 1982. The results of these tests on shielding designs for MFTF-B had an impact on the beamline design for MFTF-B. The iron-core magnet and finger assembly originally proposed were replaced by a simple, air-core, race-track-coil, bending magnet. Only the source injector needs to be magnetically shielded from the fields of approximately 400 gauss.
Date: November 16, 1983
Creator: Kerns, J.; Fabyan, J.; Wood, R. & Koger, P.
Object Type: Article
System: The UNT Digital Library
Comparison of measured and calculated uranium isotopic concentrations in cascade streams at the Paducah Gaseous Diffusion Plant (open access)

Comparison of measured and calculated uranium isotopic concentrations in cascade streams at the Paducah Gaseous Diffusion Plant

A test has been performed at the Paducah Gaseous Diffusion Plant (PGDP) in connection with studies for the US Arms Control and Disarmament Agency on the possibility of utilizing measurements of the concentrations of the minor uranium isotopes in /sup 235/U enrichment cascade external streams as a safeguards technique (MIST). This is the fourth plant test that has been performed in connection with the MIST studies, the first three having been done at the Oak Ridge Gaseous Diffusion Plant (ORGDP). The main objectives of the test were to measure the isotopic composition and flow rates of the plant external streams over a period of time; to design an appropriate plant model in the manner an IAEA safeguards team might do it and calculate the isotopic compositions of the plant streams; and to compare the calculated isotopic values with the measured ones. The calculated /sup 235/U to /sup 234/U concentration ratios in the product and tails streams did not match the average measured values in the high-power period as well as they did for the low-power period, when the same isotopic composition for natural U was assumed at both power levels - the actual composition of the natural U fed to …
Date: June 16, 1982
Creator: Blumkin, S.
Object Type: Report
System: The UNT Digital Library
Richtmyer-Meshkov instabilities in stratified fluids (open access)

Richtmyer-Meshkov instabilities in stratified fluids

We present an analytic theory of Richtmyer-Meshkov instabilities in an arbitrary number N of stratified fluids subjected to a shock. Following our earlier work on Rayleigh-Taylor instabilities, the theory assumes incompressible flow in which a shock is treated an impulsive acceleration, g = ..delta.. v delta(tau/sub s), ..delta..v being the jump velocity induced in the system by a shock at time tau/sub s/. We discuss the special cases N = 2 and N = 3, and illustrate both Rayleigh-Taylor and Richtmyer-Meshkov instabilities by examples patterned after inertial confinement fusion implosions.
Date: December 16, 1983
Creator: Mikaelian, K.O.
Object Type: Article
System: The UNT Digital Library
Waste form dissolution in bedded salt (open access)

Waste form dissolution in bedded salt

A model was devised for waste dissolution in bedded salt, a hydrologically tight medium. For a typical Spent UnReprocessed Fuel (SURF) emplacement, the dissolution rate wll be diffusion limited and will rise to a steady state value after t/sub eq/ approx. = 250 (1+(1-epsilon/sub 0/) K/sub D//epsilon/sub 0/) (years) epsilon/sub 0/ is the overpack porosity and K/sub d/ is the overpack sorption coefficient. The steady state dissolution rate itself is dominated by the solubility of UO/sub 2/. Steady state rates between 5 x 10/sup -5/ and .5 (g/year) are achievable by SURF emplacements in bedded salt without overpack, and rates between 5 x 10/sup -7/ and 5 x 10/sup -3/ (g/year) with an overpack having porosity of 10/sup -2/.
Date: September 16, 1980
Creator: Kaufman, A. M.
Object Type: Report
System: The UNT Digital Library
Acceleration of compact torus plasma rings in a coaxial rail-gun (open access)

Acceleration of compact torus plasma rings in a coaxial rail-gun

We discuss here theoretical studies of magnetic acceleration of Compact Torus plasma rings in a coaxial, rail-gun accelerator. The rings are formed using a magnetized coaxial plasma gun and are accelerated by injection of B/sub theta/ flux from an accelerator bank. After acceleration, the rings enter a focusing cone where the ring is decelerated and reduced in radius. As the ring radius decreases, the ring magnetic energy increases until it equals the entering kinetic energy and the ring stagnates. Scaling laws and numerical calculations of acceleration using a O-D numerical code are presented. 2-D, MHD simulations are shown which demonstrate ring formation, acceleration, and focusing. Finally, 3-D calculations are discussed which determine the ideal MHD stability of the accelerated ring.
Date: May 16, 1985
Creator: Hartman, C. W.; Hammer, J. H. & Eddleman, J.
Object Type: Article
System: The UNT Digital Library
Radioiostope studies utilizing a low level whole body counter and clinical application of activation analysis. Progress report (open access)

Radioiostope studies utilizing a low level whole body counter and clinical application of activation analysis. Progress report

The main emphasis of these studies is the development of methods (hardware and software) for the quantitation of body and specific organ burdens of radioactivity. Current work is directed toward the evaluation of radiation dose distributions in human beings from new radioactive tracers and new procedures used in nuclear medicine. Dosimetry and clinical studies will be carried out on patients using new radiopharmaceuticals where dosimetry data are lacking. Future efforts will be directed toward the development of systems that will facilitate the collection of dosimetry data using less specialized facilities. The availability of instrumentation and analytic techniques that provide clinical images as well as dosimetry data should enhance the rate of collection of data on human exposures in medicine and assist in the optimization of diagnostic strategies. In parallel with these efforts, we are developing a new computer assisted technique for diagnostic decision making. The basic aim is to utilize efficiently all the available data to maximize information gain while minimizing cost factors.
Date: January 16, 1980
Creator: Brill, A. B. & Price, R. R.
Object Type: Report
System: The UNT Digital Library
Technological implications of SNAP reactor power system development on future space nuclear power systems (open access)

Technological implications of SNAP reactor power system development on future space nuclear power systems

Nuclear reactor systems are one method of satisfying space mission power needs. The development of such systems must proceed on a path consistent with mission needs and schedules. This path, or technology roadmap, starts from the power system technology data base available today. Much of this data base was established during the 1960s and early 1970s, when government and industry developed space nuclear reactor systems for steady-state power and propulsion. One of the largest development programs was the Systems for Nuclear Auxiliary Power (SNAP) Program. By the early 1970s, a technology base had evolved from this program at the system, subsystem, and component levels. There are many implications of this technology base on future reactor power systems. A review of this base highlights the need for performing a power system technology and mission overview study. Such a study is currently being performed by Rockwell's Energy Systems Group for the Department of Energy and will assess power system capabilities versus mission needs, considering development, schedule, and cost implications. The end product of the study will be a technology roadmap to guide reactor power system development.
Date: November 16, 1982
Creator: Anderson, R.V.
Object Type: Report
System: The UNT Digital Library
Management of solid waste (open access)

Management of solid waste

Compliance with the latest regulatory requirements addressing disposal of radioactive, hazardous, and sanitary solid waste requires the application of numerous qualitative and quantitative criteria in the selection, design, and operation of solid waste management facilities. Due to the state of flux of these regulatory requirements from EPA and NRC, several waste management options were identified as being applicable to the management of the various types of solid waste. This paper highlights the current regulatory constraints and the design and operational requirements for construction of both storage and disposal facilities for use in management of DOE-ORO solid waste. Capital and operational costs are included for both disposal and storage options.
Date: April 16, 1980
Creator: Thompson, W.T. & Stinton, L.H.
Object Type: Article
System: The UNT Digital Library